1. Field of the Invention
The present invention relates to a technique of generating an image having a wide dynamic range by composing a plurality of images shot with different exposures.
2. Description of the Related Art
Recently, in order to implement a dynamic range exceeding the dynamic range of an image sensor formed from a CCD or CMOS, a technique called HDR (High Dynamic Range) composition is proposed. HDR composition is a technique of generating an image having a wide dynamic range by shooting a plurality of images with little highlight-detail losses and a plurality of images with little shadow-detail losses with different exposure conditions and composing them (see, for example, Japanese Patent Laid-Open No. 6-273354).
In the above HDR composition, however, when, for example, shooting a moving image under a fluorescent lamp, flickers occur in the respective frames to be composed. As a consequence, flickers also occur in the frame after the composition.